Patent Literature 1 discloses an example of a heating apparatus that is configured as a sheet heat generator. The heating apparatus described in Patent Literature 1 has the sheet heat generator that is arranged at a position corresponding to an expansion direction of an air-bag device. In addition, an interior member has a thin portion provided with a tear portion. The tear portion is broken preferentially when the air-bag device expands. The thin portion is provided in an opening portion of the sheet heat generator, in other words, at a position corresponding to a portion having no heat generator. Therefore, the air-bag device can expand from the opening portion of the sheet heat generator when a vehicle collides, and when the air-bag device is operated and expands. The opening portion of the sheet heat generator decreases a mechanical strength of a portion corresponding to the thin portion to be weaker than a mechanical strength of a portion not corresponding to the thin portion. Thus, the heating apparatus is configured not to prevent the air-bag device from expanding.